1. Field of the Invention
The present invention relates to multi component controlled release system that can be incorporated in oral care products, nutraceutical, food products and beverages to effectively encapsulate one or multiple active ingredients and sensory markers (i.e., flavors, cooling agents, sweeteners, etc.) and release multiple active ingredients in a consecutive manner, one after the other. The controlled release system of the present invention enhances the stability and bioavailability of wide range of flavors, sensory markers, and other active ingredients, prolongs their residence time in the oral cavity, controls their release characteristics, and prolongs the sensation of flavors and sensory markers in the mouth to provide long lasting organoleptic perception or long lasting mouthfeel. The invention further relates to oral care, food products, and beverages comprising the controlled release system of the present invention.
2. Description of the Related Art
Extensive effort has been directed in recent years towards controlling the release characteristics of various active ingredients flavors and sensory markers to prolong product shelf life and to prolong the sensation in the mouth during consumption of food products and beverages. Various methods and compositions have been described for providing enhanced stability and better control of the release of active ingredients and flavors in food products.
Spray drying, accounts for the majority of commercial encapsulated materials in food products. The spray drying encapsulation process is relatively simple, economical, and easily scaled to large production volumes. A major benefit of spray drying encapsulation is the broad range of actives and sensory markers which can be encapsulated. These actives include oil-soluble flavors, water-soluble compounds, natural extracts, single component flavor compounds, as well as complex compounded flavors having both water- and oil-soluble components.
U.S. Pat. No. 3,971,852 discloses the use of modified starch, gums and other natural hydro-colloids with lower molecular weight polyhydroxy compounds to yield a glassy cellular matrix with encapsulated oil at a maximum of 80 volume %. This system forms a shell surrounding the oil flavoring but is limited to lipophilic flavoring agents.
U.S. Pat. No. 4,532,145 describe a process and composition in which a volatile flavorant is fixed by spray drying from a carrier solution made up of 10-30% of a low molecular weight component such as a sugar or an edible food acid with the balance of solids being a maltodextrin carbohydrate in the amount of 70-90%.
U.S. Pat. No. 5,124,162 discloses a carrier mixture composed of mono- and disaccharides (22-45%), maltodextrins (25-50%), and a high molecular weight carbohydrate such as gum arabic, gum acacia or chemically modified starch (10-35%) to which flavoring agents are added and the subsequent solution spray dried to yield a free flowing powder with a bulk density of 0.50 g/cc.
U.S. Pat. No. 4,859,377 describes the use of amylose-containing pregelatinized starch to encapsulate entomopathogens, thereby protecting such biocontrol agents from environmental degradation and also promoting infection of target pests. The encapsulation is effected in an aqueous dispersion of the pregelatinized starch: for dry, granular products, the starch solids content of the dispersion is 25-40%; for sprayable liquid products, chemically degraded starch is used at a solids content of 1-10%.
U.S. Pat. No. 4,911,952 discloses chemical biological agents to be encapsulated are blended into an aqueous dispersion of an unmodified starch comprising about 5% to about 25% by weight amylose. The dispersion, having an initial starch solids content of about 20% by weight, is characterized by completely disrupted starch granules and completely disassociated amylose molecules that are not significantly depolymerized. Subsequent drying is accomplished by reassociation of the amylose molecules which converts the dispersion into a protective matrix and binds the agents within the interstices of the reassociating starch chains. Rate of release of agents to the environment can be altered by varying the proportion of amylose in the starch. Encapsulation of biologically active compositions provides protection against degradative environmental conditions, improves safety in handling, and slows the release of such compounds to the surrounding medium.
U.S. Pat. No. 5,183,690 discloses biologically active agents to be encapsulated are continuously blended with a starchy material and water, subjected to high-shear mechanical action at a temperature above the gelatinization temperature of starch, and continuously recovered as an insolubilized matrix of starch that entraps discontinuous domains of the agent. Alternatively, the core material to be encapsulated is added and blended with the aqueous dispersion of starch after the starch and water have been subjected to an elevated temperature sufficient to gelatinize the starch. Rate of release of agents to the environment can be controlled by pre-selecting a set of conditions related to various processing parameters. Encapsulation of biologically active compositions provides protection against degradative environmental conditions, improves safety in handling, and slows the release of such compounds to the surrounding medium.
U.S. Pat. No. 5,506,353 discloses particulate flavor composition comprising a flavor oil fixed in a particulate low cariogenic matrix of hydrogenated starch hydrolysate and a maltodextrin having a dextrose equivalent value of less than 20. A process for the encapsulation of a flavor oil comprising forming a homogeneous mixture of the flavor oil with (a) from about 40 to about 85 percent by weight of a particulate polyol consisting of hydrogenated starch hydrolysate, (b) from about 10 to about 30 percent by weight of a maltodextrin having a dextrose equivalent of less than 20, (c) an emulsifier and water, and spray-drying the resultant mixture to form a particulate product of from about 0.15 to about 0.85 g/cc bulk free flow density. Methods to confer, enhance or modify the flavor properties of a consumable edible material which comprises adding thereto the particulate flavor composition defined above; and methods to confer, enhance or modify the flavor properties of a tooth-paste base which comprises adding thereto the particulate flavor composition defined above are described.
An alternative process for encapsulation of active ingredients and sensory markers for food products is melt extrusion. In this process, a melting system, i.e. an extruder, is employed to form the carrier melt in a continuous process. The encapsulated flavor is either admixed or injected into the molten carbohydrate carrier.
U.S. Pat. No. 2,809,895 describes a process for encapsulation of an essential oil, such as lemon, lime or grapefruit oils, in a matrix comprising corn syrup, antioxidant and dispersing agent. The essential oil, antioxidant and dispersing agent are added to the corn syrup, the resultant mixture is heated to 85 degree-125 degree C. and agitated or extruded to form an emulsion in pellet form, and the resulting particles are washed with a solvent and finally dried.
Similarly, in U.S. Pat. No. 3,922,354, Galuzzi et al. disclose the use of high-shear mixing to incorporate active agents into low-water, high-solids matrices prepared from partially gelatinized unmodified starches. Additives such as modified dextrins, mixtures of mono- and diglycerides, toasted cereal solids, and coloring agents are used to control the release of active agents.
U.S. Pat. No. 4,232,047 teaches the preparation of a food supplement concentrate of an ingestible agent encased as a dispersed microphase in a matrix encapsulating medium, such as starch, protein, flour, modified starch, gum, or mixtures thereof. The concentrate is prepared by mixing the ingestible agent and the encapsulating medium with limited water to convert the mixture, under applied extrusion pressure and controlled heat. The protein exemplified is gelatin.
U.S. Pat. No. 4,230,687 discloses the application of shearing stress, vigorous mechanical working, and heat to distribute active agent into an enveloping matrix of chemically modified starches, gums, and proteins in the presence of a limited quantity of water. Proteins are used for slow-release matrices; modified starches are used for rapid release.
U.S. Pat. No. 4,420,534 describes the use of a matrix composition consisting of 10 to 30 wt % of a low molecular weight component chosen from a series of mono- or disaccharides, corn syrup solids, or organic acid with the balance of the mixture being maltodextrin. The matrix base is dry blended with an anhydrous liquid flavoring component and melted in a single screw extruder to yield a solid matrix characterized as a glass with a glass transition temperature >40° C.
U.S. Pat. No. 4,689,235 discloses an extrudable encapsulation matrix composition having improved loading capacity for oils, flavors, fragrances, agricultural chemicals, insecticides, drugs, etc. The matrix comprises a maltodextrin and hydrogen octenylbutanedioate amylodextrin or equivalent.
U.S. Pat. Nos. 4,610,890 and 4,707,367 disclose a solid essential oil flavor composition having a high essential oil content and a process for preparing the product are disclosed, the process involving preparation of a heated or cooked aqueous mixture of a sugar and starch hydrolyzate together with an emulsifier. A selected essential oil or other oil-soluble flavor is combined and blended with a mixture in a closed vessel under controlled pressure conditions to form a homogeneous melt, the melt being extruded into a relatively cool solvent, dried and combined with a selected anticaking agent to produce the stable, relatively non-hygroscopic particulate flavor composition of the invention. The selected quantity of essential oil flavor blended into the homogeneous melt being sufficient to yield about 12 to 35% by weight of essential oil in the encapsulated solid particulate composition. During the process, encapsulation efficiency is maintained preferably at or above about 60%, more preferably above about 70% and most preferably above about 75 to 80%. Also, the cook temperature for the process is preferably maintained at or below a maximum of about 126 degree C.
U.S. Pat. Nos. 4,610,890 and 4,707,367 describe a process for preparing a solid essential oil composition having a high content of the essential oil, which composition is prepared by forming an aqueous solution containing a sugar, a starch hydrolysate and an emulsifier. The essential oil is blended with the aqueous solution in a closed vessel under controlled pressure to form a homogeneous melt, which is then extruded into a relatively cold solvent, dried and combined with an anti-caking agent.
U.S. Pat. No. 4,929,447 discloses method and composition for protecting an active ingredient and providing controlled release therefore, especially in a chewing gum composition, which includes a high molecular weight polyvinyl acetate blended with a hydrophobic plasticizer which forms a film with the high molecular weight polyvinyl acetate in the absence of an added solvent therefore. The active ingredient, such as the artificial sweetener aspartame, is blended into the encapsulating composition as, for example, by melt blend which can then be cooled to a solid and ground into particulate. The encapsulated active ingredient can then be used in a composition for ingestion by a human in the form of, for example, a chewing gum with extended shelf life and highly controlled release of the active ingredient.
Encapsulation of components in a grindable, glassy carbohydrate matrix is disclosed in U.S. Pat. Nos. 5,009,900 and 5,087,461 and U.S. Pat. Nos. 5,972,404 and 6,004,594. In
U.S. Pat. Nos. 5,009,900 and 5,087,461 volatile and/or labile components, such as vitamins or flavoring components, are encapsulated in extruded glassy matrices comprising a water-soluble, chemically-modified starch having a dextrose equivalent not greater than about 2, a maltodextrin having a dextrose equivalent in the range of from about 5 to about 15, corn syrup solids or a polydextrose having a dextrose equivalent in the range of from about 21 to about 42, and a mono- or disaccharide.
U.S. Pat. Nos. 6,468,568 and 6,436,453 disclose a mineral or vitamin fortification ingredient which does not deleteriously affect palatability and appearance of foods is obtained by encapsulation of the mineral or vitamin in a grindable, glassy matrix composition. The glassy matrix composition includes an oligosaccharide, such as beta-2-1 fructofuranose materials, preferably fructooligosaccharides (FOS) and inulin, which not only forms a glassy matrix, but also beneficially increases the fiber content of the food. At least one edible oil is included in the encapsulating composition to prevent substantial adverse interaction between the mineral or vitamin encapsulant and the glass-forming oligosaccharide matrix material, and to achieve controlled release of the encapsulant from the glassy matrix. A method for encapsulating a mineral or vitamin in a glassy matrix is described comprising: a. admixing an encapsulant component comprising at least one mineral or vitamin with an edible oil to obtain a slurry wherein said at least one mineral or vitamin is encapsulated by said oil, b. admixing said slurry with a melt comprising at least one molten glass-forming oligosaccharide matrix component to obtain a molten blend, and c. cooling the molten blend to encapsulate the oil encapsulated mineral or vitamin in a glassy matrix.
U.S. Pat. Nos. 5,897,897, 6,187,351, and 6,416,799 disclose carbohydrate-based glassy matrices which are stable in the glassy state at ambient temperatures may be prepared by the use of aqueous plasticizers with melt extrusion. Such glassy matrices are useful for the encapsulation of encapsulates, in particular, flavoring agents.
Coacervation is another encapsulation technology that was commercialized in the 1950s, yields that has found wide usage in the pharmaceutical, fragrance and specialty products industries. However the relatively high process costs, sensitive multi-step batch process, regulations limiting the number of polymeric agents which can be used in food preparations, and the difficulty in dealing with encapsulates having both aqueous and lipid solubility properties has drastically limited the application of coacervation for flavor encapsulation in the food industry. A general discussion of these issues is provided by R. Versic, “Coacervation for Flavor Encapsulation,” in Flavor Encapsulation, American Chemical Society Symposium Series #370, S. Risch and G. Reneccius, Eds., Chapter 14, 1988, which is incorporated herein by reference. Coacervation microcapsule systems can be generated in the form of simple coacervates, which are derived from a single polymer species in solution. Complex coacervates, which require the interaction of two distinct and oppositely charged polymer species, are also well characterized.
U.S. Pat. No. 3,962,463 discloses the encapsulation of flavor ingredients in gelatin waxes, polyethylene and the like followed by the depositing of the encapsulated flavor particles on the surface of the chewing gum. U.S. Pat. No. 4,217,368 discloses the controlled release of a (second) sweetener which is dispersed in, enveloped by, trapped in and otherwise protected by the gum base. A first sweetener, which is relatively unprotected, provides an initial burst of flavor. U.S. Pat. No. 4,259,355 discloses a hydrolytically releasable flavor oil entrapped in gelatine, dextrin, gum acacia or modified food starch with the aid of a hydroxypropylcellulose solid suspending agent.
U.S. Pat. No. 4,230,687 discloses the encapsulation of flavoring agent in a polymeric medium using rigorous and intimate conditions of mechanical shear to mix the flavoring agent with the encapsulating medium. The flavoring agent is gradually released from the encapsulating matrix at a rate dependent upon the rate of hydration of the matrix, which in turn depends upon the particular matrix used. The polymeric matrix may be derived from natural substances such as casein, a gelatin, modified starches, gums and related materials.
Complex coacervation encapsulation, which yields oil droplets surrounded by a chemically crosslinked polymer film has been utilized for the encapsulation of cinnamon oil in chewing gums as disclosed in U.S. Pat. No. 5,266,335.
U.S. Pat. No. 5,418,010 discloses a microencapsulation process in which a solid or liquid core material is dispersed in a protein slurry, is heated to create a protein melt and then denatured to bring about encapsulation of the core material and the product of that process.
U.S. Pat. No. 6,428,827 discloses methods and compositions for improving the flavor duration in chewing gum. In a preferred form, the present invention provides matrix compositions comprising a hydroxypropylcellulose cross-linked with a multi-functional carboxylate to yield a matrix having lower water solubility than the original cellulosic material. This matrix may be ground up, have a flavor incorporated therein and used in gum compositions in which it facilitates a prolonged release of the flavoring.
Coating or fat coating is another encapsulation technique that has been employed. Conventionally, such fat coatings are applied via a fluidized bed technique. This technique suffers from serious shortcomings, such as exposure of the active agent to a vigorous air stream that will result in that significant active agents may either volatilize or oxidize under such conditions. This air contacting may occur over a long time period as the rate of fat addition must often be slow, as it is determined by the heat load the air stream can carry away. This also limits the overall productivity of fluid-bed techniques, which in turn influences processing costs and ultimately commercial utility. In addition, the protection afforded by fat coatings applied as described above, or using any method, may be easily lost when the fat-coated particle is exposed to temperatures above the melting point of the fat.
U.S. Pat. No. 3,976,794 shows sweetened coconut products coated with a powdered sugar containing particles of sugar coated in edible fat. U.S. Pat. Nos. 3,949,094 and 3,949,096 show a process for preparing various flavorings, colorants, and flavor enhancers coated with various fats and emulsifiers, the process comprising spraying condiments which are intercepted by a second spray of certain edible coating materials.
In U.S. Pat. No. 4,765,996 polished rice or barley is enriched with nutrients which are fixed in and on the grain by coating an oil/fat and/or a wax on the grains, coating the same with a hydrophilic emulsifier and further coating them with a starch-based coating agent.
U.S. Pat. No. 5,500,223 discloses an encapsulation process employs an aqueous dispersion of silica having a particle size not substantially greater than 100 nm. An emulsion is formed by high shear mixing of the silica dispersion with the material to be encapsulated and the emulsion is gelled. The process allows hydrophobic materials to be encapsulated in structures which have a high loading of the material and a good degree of imperviousness in the presence of other materials such as surfactants and mineral oils. Using the process, hydrophobic materials such as flavors, fragrances and cosmetic ingredients can be encapsulated for delayed release in a wide variety of products.
U.S. Pat. No. 6,165,516 discloses a method for producing a chewing gum with a controlled release of caffeine, as well as the chewing gum so produced, is obtained by physically modifying caffeine's properties by coating and drying. Caffeine is coated by encapsulation, partially coated by agglomeration, entrapped by absorption, or treated by multiple steps of encapsulation, agglomeration, and absorption. The coated caffeine is then co-dried and particle sized to produce a release-modified caffeine. When incorporated into the chewing gum, these particles are adapted to produce a fast release or a delayed release when the gum is chewed.
U.S. Pat. No. 4,971,797 discloses stabilized sucralose complex in a thermally stable composition by co-crystallization with a cyclodextrin. The resulting crystalline product may be comminuted to form particles of desired size for use as a sweetener component in place of or in addition to known sweeteners such as sucrose, saccharin and the like, in a variety of foods, comestibles, and oral medications. The preparation of the stabilized sucralose compositions of the present invention constitutes a molecular encapsulation of the sucralose within the cyclodextrin thereby protecting the sucralose from discoloration caused by heat.
Spray-chilling is another form of encapsulation practiced commercially. This process begins with mixing a liquid flavor into a molten fat to create a solution/dispersion. The resulting mixture is then atomized into a chamber where it is contacted with an air stream which is cool enough to cause the atomized droplets to solidify, thus forming a crude encapsulated product. The major drawbacks of spray-chilling include fat/active-agent interactions, volatilization over time of lipid soluble materials, as well as loss of volatile materials during processing.
U.S. Pat. No. 5,064,669 discloses controlled release flowable flavoring powders and processes and apparatus for preparing and using such agents, the processes comprising heating a high melting point encapsulating or enrobing material, such as a fat and/or wax and one or more emulsifiers to melt this starting material; mixing one or more water-containing flavor compositions with a texture conditioning agent; mixing the flavor compositions and texture conditioning agent(s) with the molten fat or wax to obtain a homogeneous mixture in the form of an emulsion; and chilling the flavor composition-containing mixture to provide discrete particles of solid encapsulated flavoring agent, together with the products so produced and methods for using same.
U.S. Pat. No. 6,245,366 discloses a fat-coated encapsulation compositions may be prepared by: (i) mixing an active agent with a molten fat, to obtain a slurry, and (ii) cooling the slurry, to obtain a solid mass in which the active agent is dispersed in solid fat.
U.S. Pat. No. 6,328,988 discloses polymeric micelles for encapsulation of hydrophobic molecules are provided. Methods and formulations for delivering hydrophobic molecules to a host via these micelles are also provided. Methods of stabilizing liposomes or lipid based formulations by addition of polymeric micelles are also provided.
Accordingly, there remains a need in the art to provide methods and compositions using an efficient and economical process that can be incorporated in food products and beverages to effectively encapsulate one or multiple active ingredients and sensory markers (i.e., flavors, cooling agents, etc.), enhance their stability and bioavailability, control their release characteristics, prolong their sensation in the mouth during consumption of food products and beverages to provide a long lasting organoleptic perception or long lasting mouthfeel, and release multiple active ingredients in a consecutive manner.